Switching mechanism



, 1943 A. w. HORTON, JR

SWITCHING MECHANISM Filed May 31, 1941 M/l ENTOR A. W. HOE TOMJA.

' fully energized.

Patented Aug. 10, 1943 SWITCHING MECHANISM Arthur Horton, In, South Orange, N. J., assignor to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application May 31, 1941, Serial No. 396,049

4 Claims.

This invention relates to switching mechanisms and particularly to mechanism employed to establish electrical connections, such a telephone or other communication connections.

An object isto reduce the cost and increase the utility of such mechanisms.

Heretofore such switches have been employed in which the well-known cross-bar principles were applied to mechanisms in which two groups of coils were arranged to cross each other and having contact elements located at the intersecting points of said coils and whereby the energization of a coil in one group followed by the energization of a coil in the other group caused the contact elements at the crosspoint of said coils to be energized to establish electrical connections between said contact elements. Such switching devices were generally arranged so that the coils in one group always had to be energized first as the select coil to select the row of contact elements from which a particular'set of contact'elements were to be chosen by the energization of a holding coil in the other group. The holding coil was maintained energized as a holding means to maintain the established connection while the select coil was deenergized. In these switches after a connection has been established, the energizing current for the holding coil had to be considerably reduced to prevent the energized condition of this holding coil from interfering with the subsequent energization of coils to establish subsequent connections; In a copending application by George Robert Stibitz, Serial No. 396,081, filed March 31, 1941, arrangements have been disclosed in which magnetic contact elements are specially arranged at the crosspoints of the coils so that such reductions of the energizing currents for the holding coils are not necessary and whereby a connection is accomplished by certain sequences of energization and deenergization of the select coil involved and all of the holdingcoils while the holding coil involved is maintained It is a feature of the present invention to provide a switching device of the character of these types of switches in which magnetic elements at a crosspoint ar'e'farranged to establish connections iii-response to the energization of a coil of one group as the select coil followed by the energization of a coil of the other group as a holding coil and then followed by the deenergization of the first energized coil, in which the coil serving as a select coil or as a holding coil may be chosen from either group of coils and in which the maintaining of the holding coil fully energlzed to hold the established connection will not interfere with subsequent connections established in the same manner or be interfered with by such subsequently established connections. A switching mechanism in accordance with the applicants invention may comprise connecting mechanisms arranged in horizontal and vertical rows, with the mechanism at each crosspoint consisting of two flexible magnetic springs and four stationary magnetic plates arranged so that an upper of said springs is normally in contact with an upper outside plate and the other or lower spring is normally in contact with a lower outside plate, while the other two plates are located intermediate said springs normally out of contact therewith, but with the upper and, .lower springs to the intermediate plates. A group of horizontal coils is provided with one coil for each horizontal row of mechanisms, with each coil surrounding the upper plate and one of the intermediate plates of the corresponding horizontal row, while another group of vertical coils is provided with one coil for each vertical row of mechanisms, with each coil surrounding the lower plate and the other intermediate plate of the corresponding vertical row. This arrangement of theswitching mechanism enables the energization of any coil of either group followed by the energization of any coil in the other group. and then followed by the deenergization of the first energized coil to create a magnetic flux at the crosspoint of said coils to actuate the associated springs and to open their connections with the two outside plates and close connections with the intermediate plates to establish an electrical connection between said springs and said intermediate plates. This arrangement of the switching mechanism also enables succeeding electrical connections to be established in the same manner without interfering with the previously established connections or be interfered with by the fully energized condition to Fig. 1, three horizontal coils l l}, l l and E2 have been shown and three vertical coils l3, l4 and 15 have been shown with theconnecting mechanisms provided at each crosspoint of said horizontal'and vertical coils. Each connecting mechnism consists of an upper outside plate it of magnetic material, two intermediate plates l? and I8 of r'nag'netic material and a-lower outside plate 19. 'Be'tweenthe upper plate l5 and the intermediate plates 17 and E3 is placed a magnetic contactsprlng 2t, normally making 0011- tact with plate I6 and between these intermediate plates and the lower plate I9 is placed a magnetic contact spring El normally making contact with plate l9. Theupper springs '26 -in 1 each vertical row are connected by means of a circuit 23iand the lower springs 2| in each horizontal row are connected by means of a circuit 25 so that when two intersecting coils are operated, connections may be establishedbetwe'en' the lcircuits 223 :and 1-25, foriexample; over contacts +20 an'd'=2 l through theiinterrnediate :plates 11 and E8 as will be describedhereinafter. Actual construction details of the mechanism at the crosspointmay be as shown in Fig. 2." It-will be -noted inthis'figure.that theplates ifi'and H are surrounded by the horizontal coil it while-the plates 19 =and''|8 are surrounded by the coil [3.

T0=perrnit the 'horizontalcoil iii to be Wound in this'manner, the plates liiand 19 at each crosspointare bent downwardly and then towards the back of the structureas shown at the points 2? in this*Fiig.-=2. :Each of theIcontactspringsZQ and iil may consist of a forwardly extending spring portion 2 8 tlra't may be: of non-magnetic material and a transverse portion 29 of magnetic material 'se'cured to portion 28. While no-mounting m'eans'has b'een shownzfor the plates and the conta'ctsprings, 'it should be understood that any suitable means may be provided tokeeprthese elements and the coils in proper relation to and V electricallyinsulated fromeach other. 'Each coil 'is provided "with -a oir'cuit as shown comprising a source teciinemana -a contact element miseries with thei ceifiwinding ror theenergization'of. the coil by the closing 6f the 'associated contactelemerit and for the deene'rgization of the coil :by the opening- 0f "the a'ssociated contact element. Ihe' operatienof this switching mechanism will I *now bedescribed; 'As stated, it is immaterial 'wlietl'ier the coils'ofonegroup or the other are operatedfirst*as' select coilswhile the coils of I th'e' other group' are operatedlast as holding coils #asan operating mechanismi will be aotuatedto V "e's'tabli'shea connection at a crosspoint of anen- V 'ergize'd horizontal coil'a'nd an energized vertical fcoil-rgardless of the'order' in *which they-are "energized; If it isassuined'that coil lfiis energized, first asa selct coll it will be noted that the plate 15in thec'orresponding horizontal 'row -will be in'a-"g n'etiz'ed to maintain the connection already established between this plate and spring 'iififwhile the plate l'lfwill' be magnetized to attract the spring -2| and establish a connection "betweenthis plateand spring M as well asber I tiive'riplate' 18 and this spring 2 l, while the con- 'necti'on' betw'eenspring 2l and the lower plate l9 will be ipened. Theseconditions will, of course, prevail "at the connecting 'mechanism' at each "cross'point where thisenergized horizontal .coil

-'crosses"other verticalcoils; 1f now it is assumed that the'vertical jcoil-13 is energized as a holding coil it willf'be't observedithat as the: spring 2 I has already been attracted" by plate il 'andhas been shiftedto make xj'contact with; platej -l 21', it

the plat it "will 1' b 1 -will be maintained in this position due to the magnetizing of plate [8 by coil l3. The spring which'is held attracted to plate It; on the other hand, wiil not be attracted by the magnetizing of plate !8 as the magnetization of plate 3 is not suihcient to pull the spring 2!! down awayirorn contact with lplate H3 at this time.

i However, if the horizo'n'tahcoil I9 is mow deenergi'ze'd, thecoil-lfi'being energized'wili cause plate it to attract spring 26 to make contact with plate E8. Thus, it will be seen that at this particular -crosspoint a connection is now established between the circuits 23 and 25 through spring 29,

' platesjllarid itand'spring 2i. The springs corresponding tofs'prihg ii at other crosspoints of this coil l5 anii the vertical coils such as itand l 5 willbereleased from the associated plates correspondingto plate ll. In this case, therefor-a the :coil It? acts as a select coil and coil l3 as a holding coil with the coil l3 fully energized.

as 'with'plate fl. I New;hirerxample; the horizontal icon lo ii 'jener i'z'en as ttnemtliiingi'coii, net'ized "and hold the spring 2c in its fattra en position. It, now, the V it will be noted. thatth'e spring '2 i win be attracted by tnepiatei'i and consequently it "win maize "contact with plate "r1 jseith'at a onnection-will'novvbe 'e'sta'b li'sh'edjbe- I tween trie'feir'cuits i3 and T25 through s ring 2t, plat n arid spring a. i ""I'husfin this Tease" e011 ifi'a cts as thesel'e'ct .c'oil' aiid'icoil ill a theholdmg coilwith tne coil "fie "rally energized.

l/Vhatrisclaimedisi p '1. :A "switching TClevice comprising "grou s of nnecting mechanisms.arranged iinfl'hori'zo'rital and vertical rows, each .fgrou consistin of two flexible m gnetic s ring and rom istationar'y' magnetic plates, Ia'n 'lup'perjof said springs/being normally ngcontaet with lanyup'per outsideplate and the othQf-orllower js'prilig being'norrnally in contact with'alloweroutside/platewhile theother "two plates. are located intermediate said (springs norm-allyoutofcontactwith said springs ai roup of; coils oneafor eachjhorizontal row-6f -mechanisrn, 1 each coil surrolindingj the upper .ipiagti and one oithe intermediate plates of-acorresponding horizontal-row or :saidnnechmisms, another group of coils,one for'-each;vertical row of said connections-being established lfigalfdless of he 5order inwvhich saidcoils aresenergized. g

mechanisms, each -coil surrounding rthe lower plate and the other tofisaid intermediate plates of a corresponoting vertical row ofvsaiwmechw coil in one group, any coil in the othermgroupgand ,ior' energizat-ion ofe-saidsnrstenergized coil to establkhemagnetidfiflldS :Btthe crosspoint ofssaid coils --;to actuate the associated springs a to open their connections lwith the -outsigie platesand to 1 connect sai to establi pri r-igs; with; the intermediate plates v U electrical connection between said springs through said i =-intermed -iate .-plates said switchingdevice =cornpris-ing rgroup of I connecting amechanismyarranged in horizontal and verticalarowsceachegroup cqns stinseofitwo flexible magnetic springs and four stationary magnetic plates, an upper of said springs being normally in contact with an upper outside plate and the other or lower spring being normally in contact with a lower outside plate while the other two plates are located intermediate said springs normally out of contact with said springs, a group of coils one for each horizontal row of mechanisms, each coil surrounding the upper plate and one of the intermediate plates ofa corresponding horizontal row of said mechanisms,

another group of coil one for each vertical row of said mechanisms, each coil surrounding the lower plate and the other of said intermediate plates of a corresponding vertical row of said mechanisms, to cause said springs to open their connections with the outside plates and connect with the intermediate plates to establish a circuit connection between said springs at a crosspoint of a coil of each group in response to magnetic fields produced at said crosspoint when said coils are energized and one of the coils is then deenergized regardless of the order in which these coils are energized, one of the springs contacting with said intermediate plates in response to the, energization of the first energized coil and the other spring contacting with said intermediate plates in response to the energization of the second energized coil and the deenergization of said first energized coil.

3. A switching device comprising groups of connecting mechanisms arranged in horizontal and vertical rows each group consisting of two flexible magnetic springs and four stationary magnetic plates, an upper of said springs being normally in contact with an upper outside plate and the other or lower spring being normally in contact with a lower outside plate while th other two plates are located intermediate said springs normally out of contact with said springs, a group of coils one for each horizontal row of mechanisms, each coil surrounding the upper plate and one of the intermediate plates of a corresponding horizontal row of said mechanisms,

another group of coils one for each vertical row of said mechanisms, each coil surrounding the lower plate and the other of the intermediate plates of a corresponding vertical row of said mechanisms, and means for energizing one coil of one group, for energizing a coil of the other group and for deenergizing said first coil for establishing respective magnetic field at the crosspoint of these coils to cause one of the springs at said crosspoint to be actuated by the field produced by the energization of said first coil to disconnect from its associated plate and connect with the intermediate plates and to then cause the other spring to be actuated by the field produced by said second coil and the deenergization of said first coil to disconnect from its associated plate and connect with said intermediate plates and to cause the field produced by the energization of said second coil to lock said two springs in connection with said intermediate plates.

4. A switching device comprising two groups of coils arranged to cross each other, a circuit controlling mechanism at each intersecting point of.

said two groups of coils includin two contact springs and an intermediate contacting member to which said two contact springs may be attracted to establish a connection between them, a source of current in each circuit, a contact element in each circuit for closing said circuit to energize the associated coil and for opening said circuit to deenergize the associated coil, the circuit controlling mechanism at the intersecting point of a coil of each group being arranged so that the closing of the circuit for either one of said coils attracts one of said contact springs to the intermediate contacting member and the closing of the circuit for the other of said coils and the opening of the circuit first closed attracts the other contact spring to the intermediate contacting member to establish a circuit between said two springs.

ARTHUR W. HORTON, JR. 

